During completion operations in wells, different stimulation techniques may be performed downhole, including nitrogen circulation, acidizing, fracturing, or a combination of acidizing and fracturing. Acidizing and nitrogen circulation are designed to clean up residues and skin damage in the wellbore in order to improve the flow of oil. Fracturing is designed to create fractures in the surrounding formation surrounding the wellbore to allow oil or gas to flow from a reservoir into the well. To enable the use of these stimulation techniques, perforations, or holes, may be created in a downhole casing in the wellbore. The perforations allow acid and other fluids to flow from the wellbore into the surrounding formation. The perforations may also allow oil to flow into the wellbore from fractures in the formation created during fracturing techniques.
Other stimulation operations may include using a sliding sleeve separation tool. A sliding sleeve may have gaps in the sleeve at two or more locations to allow for pumping oil from multiple reservoirs in a single wellbore without mixing the production from each reservoir.
During stimulation or completion operations, ball sealers may be injected into the wellbore to seal perforations that are capable of passing fluid from the wellbore into the formation. When a perforation is sealed by a ball sealer, injected fluid may be diverted to other areas of the wellbore. The use of ball sealers as a diversion method enables the fluid to flow deeper into the wellbore. Ball sealers may also be used in a sliding sleeve operation to seat in one or more gaps in the sleeve.